CATER: Comprehensive Alveolar and Tooth Esthetic Replacement

An alveolar ridge is the part of the jawbone which immediately surrounds and anchors the tooth socket ("alveolus"). Similar to any bone or muscle atrophying when not used, the alveolar ridge will shrink ("resorb") following tooth extraction. The volume of an alveolar ridge can be measured by both 3 Dimensional ("3D") intraoral scan and radiography, and is used clinically as a metric of oral health.

A dental implant is a medical-grade titanium screw placed into healed alveolar bone or a tooth socket following tooth extraction. It replaces the tooth root and supports the crown, or "dental cap"; an artificial tooth generally made with porcelain or surgical grade metals.

Implant success requires both sufficient bone alveolar volume and sufficient mucosal tissue to protect against biofilm-mediated inflammation, assure functional comfort and contribute to dental implant esthetics. Following dental implant placement, the alveolar ridge resorbs approximately 0.5 to 1.0 mm during the first year. Healed ridges are also often volumetrically deficient, losing up to 30% of their horizontal volume following tooth extraction.

To remedy this, peri-implant mucosal grafting has been proposed and is currently part of dental implant therapy. Both autogenous grafts (mucosal connective tissue from the roof of the patient's own mouth or "palate") and allogeneic grafts (collagen-rich grafts derived from a genetically non-identical human donor) are used for these purposes, but there is controversy regarding the effectiveness of supplemental graft use during implant treatment.

The purpose of this study is to prospectively evaluate whether including an allogeneic gum graft (PerioDerm*) during dental implant therapy improves implant health and appearance.

On the day of implant surgery, participating subjects will be randomized to either receive or not receive a supplemental gum allograft along with the implant. Participating subjects will also be asked to complete a brief (about 15 questions) oral health questionnaire.

Participating subjects will return to the clinic about 8 weeks post surgery for digital crown impressions and again at 11-13 weeks after surgery for crown placement. Participating subjects will also return to clinic about 1 year after implant placement for assessment of the implant evaluation. At this final study appointment, x-rays, a 3D intraoral scan and intraoral photographs of the implant will be obtained for the purpose of measuring alveolar volume. The health of the mucosa surrounding the implant and subject satisfaction will be measured via bleeding upon probing and completion of a brief questionnaire, respectively.

Inclusion criteria

• At least 18 years of age
• Willing and able to provide informed consent
• In need of one implant to replace a missing tooth
• At least 20 teeth in good repair and occlusion
• Sufficient bone volume for dental implant placement without required bone augmentation
• Site development (soft and/or bone tissue) performed at least 5 months before implant placement, when required

Exclusion criteria

• Current smoker
• Implant cannot be placed without bone graft
• Unable to pay for crown
• Untreated rampant caries and/or uncontrolled periodontitis
• Absence of adjacent (mesial and/or distal) natural tooth
• Uncontrolled diabetes
• Systemic or local disease or condition that would compromise post-operative healing and/or osseointegration
• use of bisphosphonates
• History of radiation in the head and neck region
• Unable or unwilling to return for follow-up visits
• Unrealistic esthetic or functional demands
• Unlikely to be able to comply with study procedures
• Unwilling or unable to provide informed consent